A wireless device in a full-duplex communication system can simultaneously transmit and receive wireless signals to support two-way communication. In a transmit path, a power amplifier amplifies a radio frequency (RF) signal for transmission. The transmit (TX) signal is routed through a duplexer and transmitted via an antenna. In the receive path, a desired (RX) signal is received via the antenna and coupled through the duplexer to a low noise amplifier (LNA). Following amplification by the LNA, the RX signal is filtered and then down-converted to baseband by a mixer. The down-converted RX signal is processed by other components to recover the received data.
In a full-duplex communication system, the transmit path can interfere with the receive path. A portion of the TX signal may be coupled from the duplexer to the receive path, resulting in TX signal leakage. TX signal leakage can cause interference in the desired signal processed by the receive path. Because the transmitter frequency differs from the receiver frequency, the TX signal leakage can be filtered. However, even with filtering, there typically remains a residual amount of the TX signal leakage, causing distortion that can spectrally overlap with the desired RX signal received via the antenna. This distortion can degrade receiver sensitivity. The desired RX signal is the signal received via an antenna, in contrast to the TX signal received via leakage across a duplexer.